The invention relates to a piston having a piston head provided with a field of rings and a piston shaft which is disposed thereupon.
A piston of this type is known from DE 101 45 589 A1. The piston has a piston head which consists of a field of rings with several ring grooves and, where applicable, a piston head combustion chamber. A piston shaft is disposed below the piston head in the direction of the motion of the piston. The piston shaft consists of two shaft wall sections supporting the piston during operation of the internal combustion engine which serve to guide the piston in the internal combustion engine cylinder. The shaft wall sections are connected to each other by rear connecting walls, where the connecting walls are not connected to the running surface of the cylinder. In the case of the piston from DE 101 45 589 A1, the connecting walls have an arched shape which may be convex, concave or consist of a combination of these arched shapes. Furthermore, in the case of this known piston, the lower edge of the field of rings in the area of the connecting walls is configured to project beyond said field of rings (excess) and is at least partially hollowed out there, so that an free space is created with the goal of saving weight.
It would be desirable to improve a generic piston with respect to its properties during internal combustion engine operation, specifically to increase its strength and long-term durability.